High speed printing apparatus



May 5, 1964 Filed May 6, 1960 P. F. KING 3,132,206'

HIGH SPEED PRINTING APPARATUS 3 Sheets-Sheet 1 May 5, 1964 P. F. KING 3,132,206

HIGH SPEED PRINTING APPARATUS Filed May 6, 1960 3 Sheets-Sheet 2 A B54679+561l Tij. E.

IN VEN TOR. /DAUL //NG- BY Wy, l Arro/ysys May 5, 1964 P. F. KING 3,132,206

HIGH SPEED PRINTING APPARATUS Filed May 6, 1960 3 Sheets-*Sheet 3 INVENTOR. UL F /f/IYG- was. /47'7'0p/vfy being advancedL I;

The delayimposed by therequirements for webnad-` are not complete;

HIGH SPEED PRINTING APPARATUS Paul F. King, Webster, N.Y., assignor to Xerox Corporation, a corporation of New York Filed May 6, 1960, Ser. No. 27,324

' 11 Claims. (Cl. 178-15) United safes Patent o j 3,132,206 e Patented May` 5` 1964 In View of the foregoing, it isthe principal object of this invention to provide an electronic hardcopy printer fof. the line advance type which operates elciently and at high speed. v

More particularly, it is an object of this invention to provide an electronic` hard copy printer in which data which have been devised vary from electrically-operated typewriters working ata maximum of characters persecond to line-at-a-time printers ,whichl are capable of printing 1,000 or 4more. `1Z0-character lines per-minute. As faster computers and data processing systems have become available `there has arisen a need for correspondingly faster printers having a speed capability far beyond that; of mechanical printers. Y v

In one existingform o f high-speed printer, aCharactron tube acts` to transforminputpulse code information into light rays of predetermined configuration. The alpha-numeric `characters `displayed on the `face of the Charactron tubejare projected onto a xerographic, printer and recorded onordinary untreatedpaper. `Thus, pulse- I codedata of electronic processors. may be converted to printed records in the form of letters, numerals, charts and graphs.

, In Vthe lCharactron tube, the electron beam is shaped to form a symbol or character by projectingA the electrons from the gun through avery small aperture lof the de,-` sired pattern. By placing several different apertures in a stencil-like matrix and selectivelydeecting the "beam relative thereto, a like `number of differently shaped characters may be obtained." As the electronbeamcontinues its passage, itis subsequently realigned and then. deflected to` the Vdesired line location of thefaceof the` tube. A display tube of this type is capable of speeds as high as one4 million characters per minute.

i l,When projecting theimage` from the `Charactron tube t onto a recording web for xerographic printing, it is the usual practice `tohold the web stationary duringthe printingofline and then to mechanically ratchet l'the web i forward for printing at the next line position; "While t this arrangement can accommodate a random printing` Vrate within a given line,` it requiresjadead` time of 'at least 20 to 50 milliseconds atwtlie `end of each linetoy allow for Vthe advance of the web. v v v v In some applications 4this restriction is notV material, in

others it impairs the efficiency of the system and in some Y `int'sances` it renders the system unworkable. In many data processing` systems havngra hard copy output printer, informationis fed to the cathode-ray character form'- ing tubeffrom magnetic tape inputor buffer storage tape units. Because` of thev dead 'time limit of conventional linefadvance mechanismavitbecornes necessaryto 'bring thesev-unitstto a stop during the time thereceivingjweb vancelcan` be avoided in certain instances byt providingfa continuously moving web. However, this introducesnew *limitations*Y into the data processing; system. `A Aprinter having a continuouslymoving#webwouldrequire that the printing ratebeyconstant at all timesrand thatan equivi alent -deadttmebet provided for all printedlineswhich ing operations fed to a cathode-ray `tube adapted to display alpha-numeric information is recorded Von a xerographic web whose movement is so controlledrelative to the operation. of

Vare attained by the use `of a character-forming cathode ray tube whose screen presentation is optically projected onto the surface .of iafmoving xerographic web. The

Vtube characterdisplay is produced by deflectionof the electron beam across `the screen thereof. When` an instruction `is received for a line advance, the beam is deflected downwardly vone line width from its `normal printing position and4 printing is continued on the new line. At lthe instant the beam is downwardly deflected, the, drivemotor for the xerographic web is enegizedfto advance the web, and as the web moves upwardly` the cathode vray beam moves inthe same direction lin synchronism, therewith. 1 Both motions are arrested when the beam is returned to its normal position; Thus, printare uninterrupted during the" advance of the web and the system is free of dead timeldelay., p

For a better` understanding of the inventionas well as other objects and further features" thereof, reference is made tothe following detailed description to be read` accordance with the invention.

ray tube incorporated in the system. v

FIG.3 illustrates the formation ofcharacters onthe xerographic web derived from the face of the tube. j

. FIG. '4 shows `in 'block diagram `form the reversible v binary counteriucludedin the electronicprinting system.

FIG. r5 illustrates schematically a" modification of the `servo system. t p FIG. 6 is a section of the Xerographic web employed in-conjunction with the servo system shown in FIG. 5.4

FIG.=`7"shows in block forma high speed electronic printing system Aadapted to print businessforms.

by. the name Charactron Referring "now to the f drawings `and more particularly to FIG. l, there islshown 4a high speed electronicrpri-n'ting system in accordancewith theinvention'including a character-forming cathode ray tube 10; 1`The"'alphanuA t :s meric `.presentationonttheffluorescent face ofrthfe tube isJ optically projected f by .means of a .lens fsystemstll tand akreilector 12 onto the surface of a xerographic recording'device, Igenerally designated by numeral 13.`

Cathode ray tube 10 may be ofthe general type` known andI disclosed forexample` in U.S; Patents 2,275,017.,` and acters and symbolsV such asn-the Cathode-Ray Read-Out FIG. l2 shows `the face of the character forming cathodeV 2,283,383. `The invention is not limited. to character-formingtubes of this type` and` j l tubesidescribed in the article by Perry 3, 1958; editionl of Electronics v v Synthesis technique.

j electronic control circuits 14 for'the tube.

V,and 33, the light image Successive code A' Ysuccessive characters v is accomplishedvbytheiields established Vby"deflection xerographicY plate inthe insulatingfmaterial y n l conductive materialZl. The photoconductive layer mayy l thereon'ofne powder particles. v Y

vbeaccomplished in' .accordance withthe teachings lofV .the

The input data is supplied to the cuitsfare of the type disclosed in the Charactron patents identiiied above and `include means 'for control' of the electron beam andlogie4 circuits which "select characters Y and produce deflection inputs for the tube control circuits.v

In the Charactron tube, a cathode-ray beamV from a'.

gun 15 is projected through a matrix 16 having .apertures These cir-kr o the cathode-rayV` tube mayk as electronic computers, automatic data processors, rnag-r netic storage units, central tiling systems and telecom-y munication networks.

patenti@ wise, ULS. 2,613,552 .known in the art of xerography.

The developed image formed of electroscopic powder` is then conveyed Vto a transferzone Where it is transferred to the surface of untreated paperV 30 taken from a roll, the paper being'v moved in synchronismwith the endless plate.' An electrode 31, which isfconnected to a highvoltage source, serves to apply an electrostatic f'charge to the paper; Y The charge is of opposite polarity to that of the powder on the image areas and is of sufficient intensity c to attract the powder and thereby transfer' the image to therein shaped lilreeletters,Y numerals or other characters I to be printed; The diameter of the beam is suicient to overlay only one of the aperturesinthe'matrixl. Selective 'oltages applied tothe deection plates 17 will cause the electron beam tube to be directed toL the desiredthe paper. Y v Y c The electroscopicpowder isfusible or thermo-adhesive and a suitable heater 32 is. provided to cause the powder imagestobe affixed to the paper and thus-form a permarient printed record of the images. Alternatively, the paper may beproyided with'a thermo-adhesive coating whichwhen heated will cause powder to adhere thereto. A cleaning brush et) is providedV in engagement with the endless'belt for removing surplus powderther'efrom sub` 1 sequent to thetransfer operation. Y

areaV on the matrix 16"'.so as to overlay aparticular shaped aperture. Theelectron beam emanating fromv matrix'lov has a cross-sectional coniiguration which matches the shape of the selected aperture.V `The shapedbeam is then directedpat the fluorescent screen18 to a location thereon controlled. by voltages configuration of theselected c harate'r;l n Y l signals from a'computer'or otherdataV applied( toV deflection elements 19. formedon the screen having the,

In the character-forming tube 10 shown in FIG. 1, the normal vertical position ofthe 'electron beam is in alignment with Vany axis X extending horizontally through the center of the tube. Thus', the beam is ordinarily deflected along axis X to produce a shown in'FIG. 2, in accordancewith the information processingdrevice establish, appropriateV selection voltages Y v whichare serially applied to the deection plates 17,' and theelectrostatic fields* producedther'eby successively degenerate 'the l variously "shaped electron-streams which Positioning of Vthe serve tol make up the total' message. l

along a line upon the display screen plates19'.'y Y, .Y v l The image displayed on the'face 18 of the'cathode-ray tube isoptically projected onto the surface of a flexible byV an outer layer of photoconductive may be constituted l Y 4 20, overlying', a backing member of be the usual material for thispurpose suchasanthracene Yand sulfurfas disclosedin theCarlson patent, U.S; k2,297,-

691, or materials Vsuch as a p1gment in aniinsulating binder One preferred .The j'continuous rollers 23,142@ and-,'25 which move'tlie belt through its becomesa threc-sidedvfor triangularxerographic plate.

Y, Theupper rollerl is driven by motor 26 coupled thereto" 4 fleet the beam to the different areas of lthermatrix to Y supplied to the tube.

y VIn the conventional character-forming"cathode-ray-tube i arrangement, the'next lineof Voutput information isV alsodisplayedalong the same axis Hencewhen copying,

Y asp-bylxerographfit is the usual practice, at the comple-V tion of a line, to ratchet or advanceV the xerographic web Y one4 liney width inpreparation for the next line presentation., `Inorder to prevent a the supply of data to the cathode-ray tube until theweb form of a continuous belt which Vas disclosed in thepatent to-Smmons et al. 11.8237913949. ,l f

photoconductorfis amorphous or vitreous .e

selenium as disclosed in,U.S ."Patent 2,753,278. 'f 1 belt is positionedabout three drum? f v VVVpath o'f-travel andare Vso arranged that therbelt in effect Y 1 occupies zits [next lineY position.

.recording arrangement, the web is l f recording is being made and is advancedl one step uponV Ycompletion of the line recording, i constituting dead time during entation is permitted. j v l l v accordance with the present invention, Whenan in- .Y

Y linepadvance, the electron beamv stationary while the the advance period which vnur cathode-rayl presstructionis received for a in cathode-ray tube 10 at the starting pointvisdeflected downwardly one Vline width to the off-center axis XA', as

Y shown in FIGl 2, and thebeamV then proceeds by horizontal deection across the Ltube characters Yconstituting the next' line of Voutput. informa- At thefsame time that ttherb'eamiis deiiected'downward'- ly thejdrive motorr 26 forA the xerograph'ic yweb is energized by a s'envo'control Vsystem to be later'described,and

by asuitable belt Z7. The endless plate is electrostatically sensitized by V,al vcorona discharge electrode 8,5V such as disclosed in the Carlson'Patent 2,588,699 or'in the Walkup patent,-U.S. 2,774,921.A

is constituted by screen-controlled coronadischarge api l pparatus'ofthe type disclosed inthe AWallmp patent, U.S`. v2,277,987 which affords -a substantially Juniforni charge under varying speeds of operation.

fj; The"sensitizedjfendless plate face vresults-fink the :formationof an electrostatic latentY fir'n'ageon' thefsurface of the plate. -f The xerographic plate 29 4wherein "theV latent Y electrostatic f; image sustained` on ythejrV thenA` movefs through a cascade-developing**apparatus Preferably. the charging means Y l l Vshifted'fto the exposure zionewhere the :projected image voffthfe cathode-ray tube i Y' surfacev ofthe plate is developed throughy the deposition This development may Yhorizontal and` ertical theweb is advanced. As thevfwcb Ztlis advanced upwardly, the cathode-rayvfbeam, which initially wasdisplacedfdownwardly oneV line width fromthecentral Vaxis xX, also is deilectedupvtfardlyv inQ-synchronism withvthe n f -fSince the beam concurrently is ,being deflected horizontally across the tubetofpr'oduce the successiongof characters thereacross, the `vector yresultant of the simultaneous ,c

v deflections of the beam isfthe s'lope'Z in'FIG'. 2. VBut since the displayof ycharacters alongtheyskew line-"Zv occurs insynchronism with the Y upward.movement` of the recording web, these characters I areformedou the'web along, a.transverse.jlin e,A asshown in FIG. Y5, which-'sk exactly parallel with thepreceding i parte@l une. Vneuralevertical deflection V0f the beam and the Ymotioirof the web `are halted simultaneously when the beam reaches'thecenterfaxis X, iat which pointY printing continues therealong until fthe'liirle'iis completed,A

or Vby any other technique succession of characters, as

displayon the cathode-ray .i Vtube duringV the .advance of theV web, itisessenti'al to halt 1 -Thuspin a conventionalV to produce the succession'of tion. Downward deiiection of the bearnfis" effected by a voltagerapplied to the deflection element lin'the Vcathode-,g ray tube. A*This element may take'the form of,a.delection .l plate or a 'magnetic Vdeflection coil.V

` It will be seen therefore during the advance `of the web and that printing `continues without interruption, the characters on thetube being so deected `vertically from their normal" center `position as to" assume` their proper line position on the moving web.

` `If a number of short lines are to be printed in sequence,

their beam may be qseveral line widths below the center of the tube gface.` Under` such Vcirclnnstances a large amount of powerwould be applied to` the motor, giving therelceivingwveba high acceleration in an effort to bring the beam back toits'norrnalrposition. The receiving web speedwouldbe quite steady when the character input rate v is constant and the linesgare of uniform length. Slhould that no dead time. occurs fore, an analog function of the digital value held in the counter at any given time.` v

i A |'1`he analog output voltage from the network `35' is applied through 1a `suitable direct-current amplifier 39 to the deflection. plates 33 of the character-forming cathode Y ray tube 10. The arrangement is such that when the value the informationinput stop abruptly the motor power would be reduced to zero. The inertia of the mechanicalVv system will of course move the' printing area above the normalfposition before the` web `comes torest. The control system lwill however raise the beam corresponding andhold the `printing position.`

Vertical spaces in the hardcopy output can be provided by transmitting Ia Series of line advanceinstructions to the printer. `A` space 'of several inches `can be `madewithout'deecting the Ibeam beyond the face ofthe tube. The verticalspacinglcapability can be 'used to advance the printing from one page to the `nent with very little loss in time. If it it desired, a special instruction can be provided towadvance` the printinglpositiona desired nurnfber of spaces within the limitsof the tube face. l,

i" We shall now considerthelstrncture andfunction ofrthe v servo control sy'sten'rfwhich acts -`tot synchronize the movement ofgthelxerogaphic, `web 'with -t-he operation of the character-formin`g cathode-ray tube, in the manner described above, to obviate waitingtime.

As shown inFIG. Lthe servo system for` controlling thejoperation'of motor26,` which' drives the Xerographic web,"includes a reversible binary counterl and a resistive de-coding. network 35lcoupled to the counter'to produceanerror signal.-` `This signal is applied to 1a position detector`36, the output of detector 36 being fed to theservomotor control lcircuit37. t' Y Thereversible vbinary counter includesha set of bistable l storage elements in cascade relation, each of which is adapted to transferback and forth between itstwo stable counted are? applied to one of lthe bi-stable elements;A Each l time that ,this element changes froml 'the state? representing binary Q, a `pulse is causedvto be sent to the second element in` the set.` VWhen thesecond.elementftransfers to 0, a pulse is transmitted to the thirdlelement` in `the cascadf'randso on -for allof-the bi-stabllef elements in the set. `"Ilhe `bi-stable elements may, for example, be inj` the formof ip-llopt-circuits,` magnetic core devices or any other known devices. `.In FIG.' I1;the` setfof bi-stable elementsxis constituted by: eight stages4 =providing,1in success; `The counter must be ofthe reversible typewherejlby by supplying subtractive `or reversepulses thereto, the count is reversed. l `An example of areversible counter is shown `inl-"1Gb 4, `the counter'comainingzaset ofcornplernentary flip-flops C1-`CS2,whichhavel `two completesets of `inter` kstt-age transfercircuitry S2. It will ,addorsubtnact depend- -ingup'on which side of the complementing flip- Hop stages fbusses are prcwided4 which disable;A

erates l' faster Y than "the counter 'hip-flops Hand" completes t jtlie"`ch'ange oflstate of the (grating busses before theiir'st counter ichangesf'state.

i One commercially available reversible lcounter suitable for thislpurpose is"Navconor`n1odel 111B, manufactured by .Navigation Computer 'Corpliof'r Philadelphia; Pa.,

this fmodel'being described in .Pulse Techniques?. `volume IIXQJNO.;3.,.publishe`d bythiscompany..1y ,.1

The;'resistive` decodingunetwork 1:35 isfconstitutedfby a bank of resistors a to h, one end of eachresistor being held in counter 34 is one-half of the maximum count, the resultant analog voltage which is developed -at resistor 38 and applied tothe deflectionfplate B3 is 'at =a level `maintaining the electron beam at its normal printing position at the center of vthe tube (axis X in FIG; 2).

`When the beam has completed v*its printing operation at the end of aline, it is reset by its control system 14 toits initial position at the start of thelinealong centraln t axis X. At this startingpoint, the control system supplies an advance pulse through an amplifier 4tlto the counter 34, which increases the count therein above the held value, which as indicated previously is oneahalfthe total count. Preferably, the value is increased by a large increment, such` as 8 `or 16, hence the advance pulse is applied not to the iirst-stage of the counter but to a higher Y stage providing the large increment. t

Assuming therefore` that` the counter holds 64 counts,

l representing one-halt the maximum value,and that the advance pulse adds 8 counts thereto,` the presence of 72 Acounts `will produce ananlog voltage causing deflection i, states upon the reception of pfulses.'The pulsesto be of the lcathode-ray beam downwardly from the center axis M to an olf-center aXisXa (FIG. 2) "spaced one line width therebelow. Y

Torensure that the advance pulse vis applied after completion of a line, a check pulse may be applied to amplifier 40 from aline digit counter 4l which provides a pulse only after the prescribed number of digits constituting a printingline has been counted. A mplier 40 is` adjusted so that a pulse is `applied to the binary counter 34 in the eventthat an advance pulse is received from control system 14 or a check pulse is received from counter 41. p y A The analog voltage from decoding network 35 is 'also applied through the position detector 36 to theservo control circuit 37 forthe motor 26 driving the Xerographic web. The positiondetectonprovides a`-control voltage as afunction of theV applied analog voltage and includes a thresholdcircuit with the mid-countanalog value as a'reference. Hence, no output is developed `by the detector until the input' analog exceedsv the mid-count value, the output being thereafter proportional to `the eX- tent Vof change above mid-count, Thus, when the beam is deflected 'downwardly one line width, a `torque is developed in the motor 26 causing the xerographic web to advance,L thedegree of torque depending on the incre#V mental value introducedinto the counter.`

. p As the web moves, subtract or reversel pulses are fed` back to the binary counter 34 andthe value held therein is, gradually reduced from the incremental value above Vluid-count (normal beam position) to the mid-count which this. reduction is `effected is as follows: t

lvaluef The manner in Motor 26 is mechanically` coupled to `the shaftlof a t'achometer 42 which produces a voltage output propr tional .to thespeed of themotor. This voltage isfc'on-` verted` into pulses by an analog-to-digital converter 43,

the number ofpulses 4yielded thereby being proportional p ,Y

to the magnitudeof the analog voltage.These pulses` are fedsubtractively into the iirststageof the binary counter.

` Thus,l as the flow of revers'epulsesact to reduce they t, I.

conuntheld in the counter fromits incremental value .above mid-count the analog voltage developed at the output of network `Slis reduced proportionately.` Conis repeated.`

Y or at anyy other predetermined value., y s Y v K In somegdata processing systems, prmtingon business current with `thefreduction in'analog voltage, the deflection voltage on the cathode-ra'y'tubev decreases andthe speed ofthe motor'is also reduced until the juncture is f reached at whichfthelcount heldin the 'counter is againl at half maximumvaluaiat which pointV the motor comes to allait and the cathode-rayibeam is'again at the'cen-v tral axis X. Y

The servo system responds tothe count'of additive pulses in the counter todevelop a torque in the servo rnotor which in turn produces subtractive pulses, these being'fedback into thecounter so as to reduce the count manually set switches that designate where an entry is-to be made in thevvbusi'ness form.vr For exampleg'if the ventry is four spaces down, the "appropriatefswitchwill betonnected to a particular stage binary counter; cluded inicontrolsys'tem Sti so as to provide an incremental;increase` above the mid-count value (normal center" therein torrtheylevel at which a null is established. TheV l l extent of motormovement and the concomitant excursion of the `cathode-ray.beam can be controllediby the incremental .value introduced into ,the counter.V i v *Y n Obviously had I32Ypuls`es been fed rinto the'counter,

Yrather vthan 8, the'deflection ofthe beam and the advance ofthe yweb would have Vbeenfar greater; In any event, printing continuesl during the advanceof the web, the

characters being displacedfromrthe central axis ofthe "cathode-ray tube along a slope until such time as the beam is returned to tube center.V From thereon printing f continues along the normal centerline until the line is completed. AWhen the line is completed, anradvance pulse is again generated and the line advanceprinting process In the servo system shown in `V1, the subtractive on the screen) suiicie'nt'to cause the beam' to shift four spaces down.' Thus, inprinting checks, the first position which isset in the position memory unit 48 may designate "thetstarting point for printing the date, thefsecond posif. tion may designate the starting point for thetnme Vofvfthe individual, etc. I i. s Y

In such a printing system the only formatinstiuction transmitted by the computer wouldbeva'single linstruction which directs the printer tofconsult the position memory Vunit for the startin'gjpoint of the next entry into the busi-` ness form. kThe position memory unit 48 transmits the Y new printing position to the verticaly and horizontal controlcircuits 50 in the sameleng'th'rf time as. would be required to print a character. In this manner many en tries can be printed into thousands ofbusiness `forms'at pulses ywhich reflect th'eadvance movernen'tof vthe web are generated by means of a tachometer ft2 operating in conjunctionwith an analog ,to digitallconv'erter43. Y An-y other technique byf which these pulses may be developed is-shownin FIGSpS and 6, wherein thexerographic end-l f less web is provided marginally with Va 'variable' density light track 44 providing a continuous series of equi-spaced Y light-'permeable areas` lSfLvery much in thermannerrrof asound track .on lm. V.A light sourcev te is positioned behind Vthe marginal track on the web and as thetweb adrandom, irregularY printing rate chosen by ther computer without the Vundue burden of formali instructions. Y

The electronic printer disclosed above in connection with recording alpha-numeric information is Y alsoll/ls'efulV in Vanalog lread-out applications.l Mostcathode-raly char,-

' the sensitive surface of Vanxerographic lweb Vand deflectvances, `lightfpulses are -projected throughV the trackV t vwhich, Vare intercepted byv a suitablefphotoce'll 47 topfov duce electrical pulses serving asV the subtractive pulses for the counter. Y' i Y i .s ,p The saineV result may beY accomplishedv by V'magnetic marksy printed along aftrack on th'e'xerographic belt, the marks being detected by a'rnagneticl pick-up head'to produce aseriesofV pulses :in the course of webadvance. In

veither casethe subtractive pulses are applied toithe countertoreverse the countftherein'untilthe null conditionis reached. ,Null may beestablished atrnid-count forms maybe the only purpose for which the electronic printer isgintended. In such cases it-is inefficient to gre-Vv quire the, computer tolsupply formal instructions to the printer Vand moreover itV entails anfadded programming starting point on a givengline. L

"they vertical deiiectiony platesl', isr provided with a set of horizontal detiectionsplates 49. Thuis,y a voltage applied froml a controljV system 5t) to fthe! vertical deiiection 4plates 33 willrcause the cathode-ray beam'rtofshift down` ing thejbeamperpendicularly tothe web ymotionto an extent proportional inthe instantaneous analog value.,V

An analog function may then be plotted byY advancing thewbeamdownwardly Vor the recording webV upwardly.

The servo control system described hereinabove canvcarry out this function with a `microa'dvanceI instruction. The

vertical advance producedrwith this instruction can'be 'Y l made a small fraction of. a normal line advance. An advance equal tothe spot dianrneterziil is a preferredV choice,

thus giving va solid line plot. 'A printer ,plotter `using this ycontrol system is 'capable of recording graphs of any y Y lengths. -Ifmultip1e Plots are, .desired mths Sam@ graph;

several points could be recorded between eachrweb adi Vance instruction.v

v The printer described Vherein is capablejof' printing at highdensityrates, as inthe case of a high speed teletype systemLorit can operate at low density rates, Yas in the t case-of printing into; business forms. `in. Yall instances a Y ,Y horizontal or vertical advance' in the printing position re- ,quires that suchrinformtion be transmitted to the printer rfrom some .unit of the data handling system. This may be inthe form of :separate leads connected .tor the printer Y lcontrol circuits orrv it maybefinme form" of coded inior-y Y mation `'transmitted `.over vthe same sets ofleads'which lcarr'y the alpha-'numeric instructions.` Several,instruc-r :tions can bereservedifrom the code system forproviding i a selection of advances of variouslength's. 4'

` While there has beenshown what areconsideredto'fbe- Y preferred embodiments ofthe invention,` it will be manifest thatrnany' chan'gesgandV modifications may be made .therein Without departing from the essential `spirit-of the' invention, For example, it isrecognizledqthat lrecording To. thi'sedjfhe cathode-ray mbe fie; inV addiiisniio' 0.11 PhOfOSenSitive materials Otherthan Xrosraphcmsm.-

f `bers `may be desirable rfor buierrstorage or, .i711 Somerin-V vytfardlylfrrom its centerlinevpositionQin the: manner pre-` I `f viously described, to, producejan advance of Vtpliefweb V20- and alconcurrentprinting operation. On theotherjhand, a voltage` applied Vfrom control systeniil to thehorizon-V stances,for`nal recording. vSpeciiicallgy, it isjunderstood that'recordingon' silver'halide'microlm, diazo or sim- "ilar, materials may be de'siredjforjtemporary bu'tferfstor-V lage, forroff-line operation or lfor permanent'storag'e'of ccmrputerv output ."data'. f It is'imended, therefore, in `the annexed claims tot coverallv 'such changes and mdilica- Y i ,tions asffa'll'withinthe-truel scope of therinvention.

the operation` of said device andsaid recorder a motor thereforgand apparatusto coordinate the operation fofsaid device and said recorder `including aI reversible binary counter, means coupled to said counter to derive an analog voltage therefrom as a function ofthe `count; held therein, means actuated by an advance signal and coupled to said deflection means and to said motor todeect said beam in accordance withsaid analog voltage to said displaced location and simultaneously to energize said motor to advance said web, means responsive to Y movement of said web to produce pulseswhose number depends on the displacement thereof and means to apply said pulses subtractively to said counter whereby as said web advances the count held in said counter is reduced and said analog voltage is reduced accordingly.

,2. A high speed electronic printing system comprising a read-out device including a cathode-ray beam tube for displaying illuminated alpha-numericv characters on a screen in response to input information and provided with voltage-sensitive deflection `means to vary the vertical orientation of the beam on said screen from "a normal location'thereonto a displaced location; a Xerographic recorder including a movable photoconductive web disposed to receive said characters from` said screen and a motor to advance said web; and `apparatus to coordinate including areversible binary counter, means coupled to said counter to derive an analog voltage therefrom as a function of the count held therein;v "a control circuit for said lweb advance motor, means responsive to said analog voltage' vertical orientation of said veach stage'of said counter to and coupled to said deflection means andA tosaid motor` control circuit to deflect saidbeam to said displaced location andsimultaneouslyto energize said motor, means coupled to said motor to produce pulses whose number depends on the" extent of web advance, means to apply said pulses subtractively torisaid counter whereby as said j web advances the count `held in said counter is reduced and said analogvoltageis reduced accordingly tocause said beam to return to its normal location, said motor being halted when said beam reaches said normal location;

3. A'high speed electronic` printing' system` comprising `a read-out deviceincluding a cathode-ray tube for displaying,illuminatedialpha-numeric characterson a screen in response to input information and provided with voltage-sensitive .rdeectionmmeans' to vary the vertical` orientation of said beam Yon said screen from a normal location `thereon/,tota displacedlocation; axerographic recorder including a movable web` disposed `to receive the chara acters from said screen and a motor to advance saidweb;

and apparatusto coordinate the operation of said recorder i including a reversible binary" counter, means coupled to said counter to derive analog voltage therefrom as afuncf tion jof the r count :held therein; a. servo control circuit for said web motor, meansjactuated by an advance signal and coupled to'said deilection meansand to said `motor a Vcontrol circuit to detiectsaid'beam Vin accordance i-,with said analog voltage to/said displaced location `and simul- {taneously `to energize said motor tachometer tot advance said web, meansv coupledtofsaid motorand an analog-to- 1 digital converter `coupled tofsaid tachometer to produce r reaches said normal location.

e A system, as set forthin claim 3,- wherein said vref pulses whose `rate dependson the speed of said motor, a; and means yto'gapply said `1 pulses subtractively` to .said L counter whereby as said webv advances the 4count held `70 versible, counterjincludes; a series of bi-stable stages and said means .to derive an analog voltageincludes a resistancenetwork having a `weighing resistor connected to produce a current proportional tothe count therein. t il 5. A system, as set forth in claim 3, wherein said` beam isz. caused Lto` occupy its normaL location when Athe, a count held in said counter is -one'half its `maximum value and wherein said beam` is deflected \tooccupy; its displaced location when an incremental count above said 'half maximum is introduced into said counter by said advance signal.

6. A high speed electronic printing system comprising a read-out device including a cathode-ray tube for displaying light images on a screen in response to input information and providewith voltage-sensitive deflection means to vary the vertical orientation of said beam on said screen from a normal location thereon to a displaced location; a Xero'graphic recorder including a movable web disposed to receive light images from'said screen and a motor to` advance said web; and apparatus to coordinate the operation of said recorder including a reversible binaryv counter, means coupled to said counter to derive analog voltage therefrom asta function of the count held therein,

said counter normallyv holding acount therein equal to Vhalf the maximum count, means responsive to an advance signal to introduce an incremental count in said counter above said half value to produce a given analog valueya control circuit for said web motor, means responsive to said given. analog voltage and ycoupledto said deflection e means and to said motor control circuit to deflect said o beam `to said displaced location and simultaneously to energize said motor, means coupled to said web to produce pulses whose number depends on the displacement thereof, means to apply `said pulses subtractively to said counter whereby as said web advances the count held in said counteris reduced and said given analog voltage isreduced accordingly to cause said beam to return to its normal location, said motorbeing halted when said beam reaches said normal location.

.7. A system as set forth in claim 6, wherein said means to produce pulses includes an optical track on said web a having a series of light marks thereon, andrphotoelectric` lmeans to scan said track as said web is advanced to ing on business forms and including a switching matrix- -coupled to said reversible counter selectively to introduce counts therein effecting displacement of said beam to predetermined format positions on said Web.

10. A high speed electronic recorder to record information represented by.electrical information signals comprising: a n

a ycathode rayl tube adapted anddisposed relative a sensitive member to form'marks in accordance with the information signals on the sensitive member, `the 'cathodey ray tube including horizontal deflection mean's'to derlecttthe marks transversely across the.

member and vertical deliection means to-deflect the marks longitudinally along the` member,

advance means to longitudinally advance the sensitive member, l

w means to receive` an advance signal ordering an arbitary longitudinal advance of the Ysensitive member to Va l new-position, f e a r means to develop an errorsignal representative of the diiference between the instantaneous longitudinal positionof the sensitive member andthe new position ordered by the'advance signal,

r means solely responsive tothe error signal to operate "v the" instantaneous longitudinal-1 position 'c f{t1:le.se11.4 sensitive member and in which theV sensitive memberv is lsitivevI'nember andthe psitionrqere'clby the ad-,- plivtqcondctiv; "1 f` Vance Slgnal, i Y. 5v References Citedin theflerof'this partent 'I and means responsivet) the-errorfslgnal to actuatethe'y r, q f ,1. l y r f UNITED -STATESPATENTVS Yadvance means m adirectio 4to jreducethe encorV Y 11 ,Y 12 v the vertical deeotio11-r means to ldeflect the marks av 11. Apparatus accordingl to claim 10 in which the cathlongitudinal' distance equal to the difference between' ode ray tubeforms light images which` are fgeused 011th@ lsignal whereby/5 to record i11forfr`nati-on,` marks maybe '2,729,773 Steele Ian. 3,; 1956 j instantaneouslyland arbitrarily vpositiorns'dbrithe sen 2,73j677.0 ,'McNaIiey 1 Feb. 28, 1956: sitivememberand whereby thermalfksa're'formed'in 10 -258555391 `I-Iooyel- 'Oet- 7, 19158;

i aStfaightline'intheab'sencfadvan Signals( "29015374: z.` Gundiach 1 Y 'Aug;25',1959.

UNITED STATES PATENT OFFICE CERTIFICATE 0F CORRECTIGN Patent No. 3Y 132,206 May 5, 1964 Paul F., King lt is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as:i corrected below.

Column l, line 17, for "version" read versions column lO, line 16, for' "provide" Signed and sealed this 6th day .of April 1965.,

(SEAL)V Attest:

ERNEST W. SWIDER EDWARD J. BRENNER nesting Officer Commissioner of Patents UNITED STATES PATENT OFFICE CERTIFICATE 0F CORRECTIGN Patent No. 3, 132,206 May 5, 1964 Paul E". King It is hereby certified that error appears in the above numbered patent requiring correction and that the Said Letters Patent should read asoorreoted below.

Column l, line 17, for "version" read versions column 10, line 16, for "provide" read provided Signed and sealed this 6th dayl `of April 1965. I

(SEAL)A Attest:

ERNEST W. SWIDER EDWARD J. BRENNER At testing Officer Commissioner of Patents 

1. A HIGH SPEED ELECTRONIC PRINTING SYSTEM COMPRISING A READ-OUT DEVICE INCLUDING A CATHODE-RAY TUBE FOR DISPLAYING LIGHT IMAGES ON A SCREEN AND PROVIDED WITH DEFLECTION MEANS TO VARY THE VERTICAL ORIENTATION OF SAID BEAM ON SAID SCREEN FROM A NORMAL LOCATION THEREON TO A DISPLACED LOCATION; A RECORDER INCLUDING A MOVABLE WEB DISPOSED TO RECEIVE THE LIGHT IMAGES FROM SAID SCREEN AND A MOTOR THEREFOR; AND APPARATUS TO COORDINATE THE OPERATION OF SAID DEVICE AND SAID RECORDER INCLUDING A REVERSIBLE BINARY COUNTER, MEANS COUPLED TO SAID COUNTER TO DERIVE AN ANALOG VOLTAGE THEREFROM AS A FUNCTION OF THE COUNT HELD THEREIN, MEANS ACTUATED BY AN ADVANCE SIGNAL AND COUPLED TO SAID DEFLECTION MEANS AND TO SAID MOTOR TO DEFLECT SAID BEAM IN ACCORDANCE WITH SAID ANALOG VOLTAGE TO SAID DISPLACED LOCATION AND SIMULTANEOUSLY TO ENERGIZE SAID MOTOR TO ADVANCE SAID WEB, MEANS RESPONSIVE TO MOVEMENT OF SAID WEB TO PRODUCE PULSES WHOSE NUMBER DEPENDS ON THE DISPLACEMENT THEREOF AND MEANS TO APPLY SAID PULSES SUBTRACTIVELY TO SAID COUNTER WHEREBY AS SAID WEB ADVANCES THE COUNT HELD IN SAID COUNTER IS REDUCED AND SAID ANALOG VOLTAGE IS REDUCED ACCORDINGLY. 